石羊河流域土地利用结构合理性评价

目的]评价石羊河流域土地利用结构,为石羊河流域土地利用总体规划的修编、土地利用机构的优化以及土地资源的可持续利用提供依据。方法]利用解译的石羊河流域5期(1980,1995,2000,2006,2012年)土地利用数据,基于TOPSIS方法,采用熵值法确定指标权重,结合灰色关联度分析,对石羊河流域土地利用结构的合理性进行综合评价。结果](1)5期石羊河流域土地利用结构合理度总体上较高,均在75%以上,在时间上总体呈波动上升趋势。其中,2006到2012年上升19.54%,增幅最大;(2)不同土地利用类型变化对土地利用结构的合理性影响不同,其土地利用结构合理性关联度依次为:未利用土地(0.973 8)林地(0.961 1)草地(0.950 4)耕地(0.935 2)居民用地(0.757 6)水域(0.709 0);以石羊河流域耕地为参考数列,对影响耕地的其他土地利用结构进行了灰色关联度分析,发现对耕地影响最大的是林地(0.938 5)和未利用地(0.935 0),其次是草地(0.902 1),再次是居民用地(0.797 7)和水域(0.722 9)。结论]限制石羊河流域未利用土地的开发,保护林地,调整草地和耕地比例,控制居民地的过快增长和严格保护水域,对优化石羊河流域土地利用结构具有决定性的作用。

Assessment of Land Use Structure Rationality in Shiyang River Basin

Objective] We evaluate the land use structure in Shiyang River basin in order to provide basis for editing and reversion of the land utilization plan ,and the optimization of land use structure and the sustain‐ability of land resources .Methods] Based on the land use data in the year of 1980 ,1995 ,2000 ,2006 and 2012 in Shiyang River basin ,the rationality of land use structure was assessed by using coefficient of entropy and TOPSIS (technique for order preference by similarity to ideal solution ) method and GRA (grey relational analysis) .Results] (1) The rationalities of land use structure in Shiyang River basin were above 75% ,and showed a fluctuated upward tendency . During the period from 2006 to 2012 ,it increased by 19 .54% . (2) Different land use types had different effects on the rationality of land use structure . The correlation with the land use structure rationality showed :unused land (0 .973 8) > woodland (0 .961 1 ) > grassland (0 .950 4)> cultivated land(0 .935 2) > residential land(0 .757 6) > waters (0 .709 0) .Took the farmland as the reference ,the gray correlation degree analysis showed that the greatest impact were woodland (0 .938 5) and unused land(0 .935 0) ,followed by the grassland (0 .902 1) ,and then the residential land(0 .797 7) and wa‐ters(0 .722 9) .Conclusion] To restrict the utilization of the unused land ,protect woodland ,adjust the ratio of grassland and cultivated land ,and control the excessively rapid growth of residential land and protect water ,are of great importance in optimizing of the land use structure in Shiyang River basin .